I might add that this behaviour started when upgrading from the last beta to the RC, and survived when upgrading to the definitive december FOSS version.
I have a similar other server, same OS, same...

When enabling AV/AS, on a certain server (5.0, upgraded to last version today) I have a runnig problem wih AMAVISD: amavisd runs on 100% processor, and seems to hang continuously. All mail is getting...